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PREFACE
This is a translation from the Spanish booklet C o m o Imprirnir
Carteles, publication Number 4 of CREFAL (Regional Fundamental Education Centre for Latin America), Patzcuaro, Alexico.
T h e process of printing described, though primarily adapted to
the quick and cheap production of posters, can be used for
other display and craft purposes, The simplicity and economy
of the process and its adaptability to the needs and conditions
of fundamental education workers has persuaded Unesco to
make it known to as many as possible in printed form.
In doing so, it is the sole wish of Unesco that anyone w h o
finds that the process here described corresponds to his needs
may feel completely free to use and adapt it, without seeking
permission from anyone. At the s a m e time Unesco would be
interested to hear from those w h o do so in what ways they
have found it useful and what refinements, modifications or
extensions of the system they have developed.
CONTENTS
Page
Foreword .................................................
Brief Description of the Process ........................
11. Materials, Equipment and Tools. ........................
111. The Process for Preparing the Printing Plate.. . . . . . . . . . . .
IV. The Printing Process ..................................
V. Application to Fundamental Education ....................
I.
- 2 -
3
5
7
12
20
27
FOREWORD
T h e Fundamental Education Centre for Latin America (CREFAL)was established at
Patzcuaro, Mexico, in April 1951. It is a joint effort, in which Unesco and the other
Specialized Agencies of the United Nations collaborating ,with the Expanded P r o g r a m m e
of Technical Assistance, the Organization of American States and the Mexican Government are all participating. Its purpose is to train leaders in Fundamental Education,
and in the production of fundamental education materials. for work in the Latin
American States.
With regard to the production of educational materials, the founder bodies recognized the necessity of producing new materials and, m o r e particularly, of devising new
methods for the production of materials capable of satisfying the needs of teachers
working in technically backward areas.
H o w could graphic material be produced at a m i n i m u m cost and with very cheap
equipment? This was one of the problems confronting the Centre f r o m the very beginning. Nevertheless, an even m o r e important problem was to find a method within
the technical capabilities of teachers w h o are not professional printers. Moreover, it
w a s necessary to devise a method requiring only materials which can be easily found
in any region.
In January 1952 the Centre's Production Branch began to carry out a series of experiments for that purpose. In February, w e produced our first poster at the Centre,
by means of a process which w e had been testing since 1940. Since February, when
w e produced our first poster, w e have learnt m a n y new facts that have enabled us to
improve our work. There is no doubt that, as w e acquire m o r e experience, w e shall
be able to improve the process still further.
W e have already produced nine posters of various sizes in editians containing from
50 to 1,000 copies. W e are now in a position to state that our method offers m a n y advantages, particularly from the practical point of view.
T h e present booklet is intended as a technical guide for teachers interested in this
type of graphic production.
J.O.
- 3 -
VlEJlTO... P E R 0
APREN DIE NDO
n
Poster made for the Literucy Campaign
(80x56 cm., in one or two co.!ows). It
represents a local theme: the aviejito~
(little old man) is a typical character
of a traditional folk-dance of the region.
- 4 -
I. BRIEF D E S C R I P T I O N OF THE P R O C E S S
The process of printing from a glue plate is a relatively simple one.
can use it successfully.
B y following instructions, any teacher
It consists of two fundamental elements: a wax plate on which the picture to be reproduced is engraved, and
a glue plate which is cast in the wax matrix.
T h e glue plate, after it has cooled and solidified, serves as the
printing-plate.
T h e wax plate is m a d e by pouring a mixture of paraffin wax and beeswax on to a glass pane so as to form a
m o r e or less uniform layer, 3 m m . thick.
T h e picture to be reproduced on the poster is drawn and engraved on this wax plate, thus giving a wax cast
(fig.1, see.below).A mixture of glue and glycerine, melted in a double boiler, is then poured over the w a x cast so
as to cover it with a layer, 2 c m . thick (fig. 2). After cooling, for approximately eight hours, the glue becomes
consistent and flexible like soft rubber.
The glue plate is removed by raising one end of the solidified layer (fig. 3). T h e latter Is lower surface, on
which the wax engraving has left an impression, is the printing glue surface or printing-plate (fig. 4).
This short description is intended to give a very general idea of the work involved in making a glue plate. W e
shall now describe in detail the materials and equipment required for this method of printing, as well as the entire process of producing a poster in this fashion.
0
-/
cI
GLUE
ENGRAVED LINE
J
GLUE PLATE, FACE UPWARDS
REMOVING GLUE PLATE
- 5 -
11. MATERIALS, EQUIPMENT A N D TOOLS
MATERIALS
For the wax plate, beeswax and paraffin wax are required. For the glue plate, glue, glycerine and plasticine are necessary. These materials must satisfy the following conditions:
1.
Beeswax.
2.
Paraffin wax. M a y be of any quality. (In the chapter dealing with the process in detail, it
is indicated that the paraffin wax and the beeswax are mixed in the proportions that are necessary for obtaining the desired consistency. If necessary, these materials can be replaced by candles similar to those used in churches. Care must be taken to see that the
candles are really m a d e of beeswax and not of animal fat or petroleum.)
3.
Must be pure.
Glue. Any glue (gelatinous)is suitable.
good for this purpose.
T h e glue commonly used by carpenters is very
4.
Glycerine. This m a y be of any quality; but it is preferable not to use pure glycerine, for
the latter, purchased from a chemist, is unnecessarily expensive.
5.
Plasticine. M a y be of any quality. If there is no plasticine, clay ( m a d e with soil and
water) can be successfully used in its place, but the clay must be kept d a m p .
- 7 -
ENGRAVING TOOLS
,
Gouges. FigureA,seebelow, represents the cutting edge of the gouge used for engraving linoleum
or wood.
1.
Types B and C are also used and can be easily m a d e . It is simply necessary to take a strip of
metal such as is used for wooden boxes and to fashion it so as to obtain either of the cutting edges
indicated. A wooden handle is affixed to the other end. T h e three sides of the cutting edge are
then sharpened.
Type A is a true V-shaped cutting edge. It produces very fine lines. Types B and C have a
small transversal segment which produces m u c h broader lines. A transversal segment of a
width of 2 m m . or 4 m m . is very suitable for types B and C.
Nevertheless, the artist m a y vary the width of the cutting edge if he so desires. Types B and C
m a y also be m a d e with iron, which is fashioned with a file. Steel is not necessary, for the w a x
is soft and so the edges do not wear away.
Cleaners. These are used for cleaning the lines engraved on the wax. A cleaner can be m a d e
with a thick nail affixed to a handle. T h e other end is filed so as to resemble a pencil-point, but
it must not be too sharp. Figure D represents a very good type of cleaner, whereas that shown
by figure G would not give satisfactory results.
2.
In order to m a k e wider-pointed cleaners of the type indicated by figures E and F, the point is
truncated with a file, care being taken to see that the truncated end is cleanly made.
3.
A small knife with a thin, sharp-pointed blade
4.
A brush (medium-sized with bristles) to remove wax shavings which form during the process of
engraving.
v v v
A
B
C
D
- 8 -
E
F
G
ACCESSORIES
1.
-
2.
A double boiler for melting the glue and a stick for stirring it.
3.
A stove (gas or electric, or any other form of stove).
port the pot, and m a k e a wood-fire under it.
4.
T w o strainers: one for the wax and the other for the glue.
piece of gauze can be used.
5.
A mason's level, approximately 30 c m . long.
A pot for melting the w a x and a stick for stirring it.
At CREFAL w e use three stones to supIf there are no metal strainers, a
EQUIPMENT FOR GLUE PLATE I M P R E S S I O N S
T h e equipment includes: a number of accessories; the table for the engraving of the w a x and the casting
of the glue plate; the printing-press.
W e shall describe each of them, and the manner in which it is used.
T h e size of the various materials m a y vary and depends on the type of work for which they are intended.
A large printing-press can also be used for printing small posters. T h e experiments carried out at CREFAL
have shown us that it is advisable to construct two presses of different sizes: one of rectangular shape (95 x 70
c m . )and a smaller one, one-fourth of the size of the former (35 x 47 c m . ). Sometimes, .when posters are urgently needed and the materials are not available, it is possible to obtain good results without them. If only
one or two impressions are needed each year, there is really no need to construct any equipment.
- 9 -
ENGRAVING T A B L E S
T h e engraving table is used for the engraving of the w a x and the casting of the glue plate.
W e give the following brief account of the process in order to m a k e the description of the table easier to
follow: the surface of the table, which must be perfectly level, is covered with a layer of wax; when the latter
has solidified, it is engraved with the gouge. T h e molten glue is then poured into this matrix. W h e n the glue,
which must fill all the interstices in the wax engraving, has also solidified, it is removed from the latter in the
form of a plate.
This glue plate is the printing-plate.
T h e table on which this work is done is illustrated (see below), and is constructed as follows:
It is afour-legged table with a glass top (B)surrounded with a wooden frame (A). T h e glass must be
thick and solid.
At the bottom of each leg there is an adjustable screw (C)for ensuring the correct level of the table.
In the middle of the glass top there is a transversal support (D)which prevents the top from sagging under
the weight of the cast.
Approximately 15 c m . below the glass top there are transversal supports for four electric bulbs (E)
which are intended to provide light and heat.
T h e height of the table is adjusted to suit the engraver.
When small posters are being made, it is not necessary to construct the entire table.
E
0
B.
?A
/
- 10 -
There is another type of engraving table, which is illustrated (see below).
It is convenient for small engravings and its advantages are that it is easy to transport and can be m o r e
readily adapted to the needs of the engraver.
It consists of:
A thick glass pane (A)within a wooden frame (B)(fig. 1).
A box (fig. 2) with four electric bulbs (C)arranged in the manner indicated. T h e bulbs are intended to
illuminate the glass from below and to provide heat.
T h e framed glass pane and the box for the lamps are separable from one anobher .
T h e angle at which the framework is placed depends on the difference in height between Y and Z. This
difference can be varied in order to suit the convenience of the engraver.
Figure 3 shows the framed glass pane placed, in a suitable position for work, on the box containing the
lamps.
T h e dimensions (indicated by X) of the frame and of the box must be identical, as this permits the engraver to place the frame on the box in any position.
The groove (D)which runs around the box enables the frame to be firmly affixed to the box.
I
Pxl
i
/D
- 11 -
III. THE PROCESS FOR PREPARING THE PRINTING PLATE
First stage
- PREPARATION OF THE W A X PLATE
T h e glass top of the table is first carefully cleaned.
.
Before the molten wax is poured over it, it is heated by means of the electric bulbs placed underneath.
If there is no electric current, the bulbs m a y be replaced by any other source of heat; but the latter must be
uniform and not very intense.
T h e glass pane must be perfectly level, so as to ensure that the molten wax will spread evenly over
it.
T h e size of the wax plate is fixed by surrounding the surface which it is desired to use with "walls", one c m .
high. T h e latter can be m a d e with plasticine, clay or pieces of wood. These "walls" are intended to prevent the
Iiquid wax from spreading beyond the desired limits.
The wax for the plate is prepared by melting beeswax and paraffin wax together. It is ,difficultto determine the
exact proportion of each. Experience has shown that satisfactory results are obtained if they are used in equal
quantities. If it is desired to vary these proportions, the following should be taken into account: when a greater
proportion of beeswax is used, the mixture is m o r e elastic and glutinous; whereas, if a greater proportion of paraffin wax is used, the mixture is harder and m o r e brittle.
Through experimentation, it is possible to obtain a mixture which. when it solidifies, can be easily engraved
with a gouge.
T h e engraver should therefore experiment with different proportions until he finds the mixture most suitable
for his work.
W h e n the mixture of beeswax and paraffin wax has been melted, it must be allowed to cool slowly until there is
no risk of its breaking the glass pane owing to its temperature.
While it is still liquid it is rapidly poured over the glass pane so as to cover the latter with a uniform layer .The
thickness of this layer can be varied according to the nature of the work and the type of drawings to be reproduced:
3 m m . is sufficient.
Although it is convenient to m a k e a wax plate of uniform thickness, this is not absolutely necessary; any variations that might occur in this respect will not affect the printing surface which is in contact with the glass pane.
W h e n the wax has been poured over the glass pane, it is allowed to cool until it solidifies: twenty or thirty
minutes are sufficient for that purpose.
Second stane
- DRAWING
OF THE W A X
T h e drawing which is to appear on the poster is delineated on the wax plate. It m a y be drawn directly on the
wax or traced from a paper drawing.
N o special paper is needed for tracing. The paper drawing is placed on the wax and it is lightly traced with a
pencil or s o m e other pointed instrument. In this way the drawing will be softly reproduced on the wax surface.
This method of tracing is most convenient when the engraver is unable to draw, as it permits any drawingwhatsoever to be reproduced.
A s already indicated, it is also possible to draw directly on the wax. In this case, it is necessary to use a soft
pencil or Indian ink. One of these must also be used in order to give greater relief to drawings thathavebeentraced.
-
-
T h e drawing whatever the process used will appear on the wax plate in the form of black lines and surfaces.
In general, the technique to be used is the s a m e as that employed for engravings on linoleum or wood, the only difference being that, in the case of wax, it is necessary to carve out everything that will appear on the poster,whereas, in the case of linoleum, those parts are cut out which will not appear on the poster.
A s everything that is to be reproduced is cut out, it is easy to reproduce drawings consisting mainly of lines.
It is not necessary to "engrave in reverse". T h e letters are engraved on the wax from left to right, in the s a m e
way as w e read them.
Third stage
- THE
ENGRAVING ON THE W A X
T h e lines drawn cm the wax are carved ou-t with a gouge, particular care being taken to see that the latter cuts
right down to the glass. Each time this occurs, the engraver forms a printing line or surface.Although the lines
appearing cm the glass pane are very fine, they should he eut out in the form of a V, in order to facilitate the casting of the glue plate. This is illustrated on page 5 : figure 1 represents a line engraved on the wax by a gouge;
figure 2 shows how the filling of this engraved line with the glue is facilitated by the V-shape of the former.
- 12 -
-
-
W h e n several fine lines are cut very close together in order to obtain grey tones, for instance there is a
risk of the wax detaching itself entirely f r o m the glass pane. This can be avoided by lighting the electric bulbs and
slightly warming the wax before engraving the fine lines. T h e w a r m wax is less brittle and adheres m o r e firmly to
the glass pane.
O n the other hand, if it is desired to remove a piece of the wax plate in order to leave a printing surface,this
can be done without any difficulty. It is simply necessary to cut around the surface in question with a small knife
and the piece of wax can then be prized from the glass pane. This will produce a dark surface on the poster. If the
w a x is cold, it is m o r e brittle and so the piece to be removed can be easily detached from the glass pane.
This is the best process for the engraving of letters, particularly if they are large block letters.
If the engraver wishes the wax engraving to stand out clearly, he should place a black paper underneath the glass
pane. The lines of the engraving will then appear in black,and the rest will remain invisible owing to the opacity of
the wax.
If an error is m a d e during the engraving, it can be "erased" as easily as errors in a-paper drawing.For that
purpose, it i's sufficient to melt a little wax with a match and to let it drip into the engraved line which it is desired
to correct. W h e n this wax solidifies the correction can be made.
As the printing surface is in contact with the glass pane, the clarity of the lines on the poster will depend on the
cleanness of the glass. Consequently. the latter must be cleaned with considerable care.
If the glass pane has a large surface, it must be kept clean by vigorously rubbing it with a d a m p piece of cotton
fabric. If it is only desired to clean engraved lines, the cleaners already described must be used.
T h e cleaner must be passed several times over the lines so as to leave the glass perfectly clean. It must be
used vertically in order to produce satisfactory results.
W h e n the lines have been cleaned in this manner, the rest of the wax plate must be brushed in order to remove
all the wax shavings remaining on it.
W h e n large parts of the wax plate are not engraved (they will appear as white surfaces on the poster), the thickness of the wax must be increased. Figurel(seebe1ow) shows two engraved lines separated by a large space; in order to increase the thickness of the wax(represented by stripes).plasticine(represented in figure 2 in black) is added. W h e n the glue is poured over the wax (figure 3) the space occupied by the plasticine makes a deeper hollow between the engraved lines; this is clearly seen when the glue plate is removed from the wax engraving (figure 4).
Figure 5 shows that, even if the paper sags owing to pressure or its o w n flexibility, it will not be stained by
the glue plate, provided that the hollow has been m a d e sufficiently deep.
PLASTICINE
GLUE
,
PA P E R
Fourth stage
- PREPARATION OF THE TABLE
W h e n the wax engraving is ready to receive the glue, the surface to be covered by the latter must be limited, as this surface will determine'the size of the printing plate.
A wooden frame, 2 c m . high, or a "wall" ( m a d e with plasticine or clay) of the s a m e height can be used
in order to prevent the liquid glue from spreading beyond the said limits.
T h e height of the frame or of the "wall" will depend on the thickness which it is desired to give to the
glue plate. A thickness of 2 c m . is suitable for plates which do not exceed one square metre. T h e larger the
plate, the thicker it must be, so that it will have the necessary resistance.
*If a wooden frame is used to prevent the liquid glue from spreading, care must be taken to see that no
spaces are left between the wood and the w a x into which the glue might work its way. It is advisable to strengthen
the framework by filling all the cracks and chinks in it with plasticine. In order to prevent the glue from adhering to the framework, the latter should be smeared with oil or grease.
Fifth stage
- PREPARATION
OF THE GLUE MIXTURE
The solidified glue plate is the printing-plate. This plate is m a d e with a mixture of glue and glycerine.
A n y sort of hard gelatinous glue can be used. T h e glue commonly used by carpenters and which is supplied in
sheets of 8 x 20 x 112 c m . (thickness) is suitable and can be procured anywhere.
-
-
Where a choice is possible, the finest and purest glue should be used.
In order to determine whether a sheet of glue contains dust, it is sufficient to look at it against the light.
The sheets of glue must be broken into small pieces; before being broken with a h a m m e r they should be
placed in a sack in order to prevent the pieces from scattering.
After it has been pounded, the glue is placed in a pot, covered with water and allowed to soak for four
hours. T h e glue absorbs part of the water and the rest of the latter evaporates during the four hours.
T h e glycerine is added to the glue which has absorbed the water: one litre of glycerine to every five litres
of glue.
The mixture is placed in a double boiler until the glue and the glycerine are transformed into a thick,
glutinous liquid.
T h e quantities given of glue and glycerine must not be regarded as invariable.
The correct proportions depend on m a n y factors, and it is advisable to experiment with small quantities
in order to determine what proportions correspond to the particular needs of the climate, temperature, etc.
The two main factors are the quality of the glue used and the temperature of the region in which the work
is done. Heat tends to soften the glue plate, and cold to harden it.
T h e glue plate must maintain the consistency of soft rubber.
If, after the first experiment, the glue plate is still very hard, glycerine should be added. If it is too
soft, m o r e glue should be added.
T h e mixture of glue and glycerine must be heated in a double boiler until all the pieces of glue have
melted and formed a uniform liquid. T h e mixture must have the s a m e consistency as thick cream. If, in its
liquid state, it is too thick, m o r e glycerine should be added.
Before being emptied, the pot of glue must be removed from the double boiler and allowed to coo1,while
the mixture is being constantly stirred. It must be allowed to cool sufficiently to avoid its melting the wax when
it is poured over the latter. A good m e a n s of ascertaining this is to place one's finger in the liquid glue. T h e
glue must be w a r m but not hot enough to burn the finger. If it is possible to keep one's finger in the glue for half
a minute, the glue is ready to be poured out. Care must be taken that the glue does not cool too much, for it
then begins to thicken.
- 16 -
This mixture of glycerine and glue is similar.to that used for making printers' rollers. T h e latter are
m a d e in all parts of the world and it is easy to obtain advice on them from the local printers. T h e manufacturers
of rollers are familiar with the characteristics of the local glue and know what quantities of glue and glycerine
must be used in the mixture if the latter is to correspond to the climate of the region concerned.
Sixth stage
- CASTING
OF THE GLUE PLATE
This operation must be carried out with considerable care, for the accuracy of the impressions depends
upon it.
First of all, the table must be m a d e perfectly level. and for that purpose the mason's level already referred to must be placed directly on the glass pane. T h e uniformity of thickness of the glue layer will depend on
the level of the table. Experience has shown that, in making impressions, the uniformity of thickness of the
printing-plate is of fundamental importance.
In order to obtain the correct level, the table is provided with adjustable screws as indicated on pagelo.
T h e liquid glue will then find its o w n level.
T h e glue must be stirred before being poured out and care must be taken that it does not
hard pieces or foreign matter.
contain any
Before pouring out the glue, the edge of the glue pot should be placed very close to the glass pane so that
the glue will not cool while it is being poured out. It should be poured out slowly, to ensure that it will fill all
the interstices in the engraving. If the glue is poured out rapidly, air-bubbles m a y form and so prevent the liquid mixture.from finding its way right down to the glass pane. That is why the gouge with a V cutting edge has
been recommended; as the glue is thick, it might not be able to penetrate to the glass pane if the upper part of
the engraved lines were too narrow, and, as it is the glass pane which determines the printing surface, any airbubbles which might form would create a white area on that surface.
In order to avoid this, it is useful, when pouring out the glue, to give short, rapid taps on the lower surface of the glass pane, and thus facilitate the penetration of the glue.
Another risk is that the glue, on cooling, m a y solidify near the edges before penetrating throughout the
whole of the engraving. This can be avoided by moving the glue pot from one side of the glass pane to the other
when pouring out the glue.
After pouring out sufficient glue to cover the engraving, one can pour the rest out rapidly until the layer
of glue attains the required thickness.
T h e glue plate solidifies after it has been allowed to cool for six or eight hours. It is useful to allow it to
cool overnight.
It is important to carry out the whole of this printing process in the dark. T h e materials utilized are
very sensitive to heat, and the direct rays of the sun affect them immediately.
Seventh stage
- REMOVAL
OF THE GLUE PLATE
After the glue has been poured over the wax cast and has solidified, the glue plate obtained must be separated from the cast.
For that purpose, the edge of the glue plate is carefully raised from the surrounding "wall". If the latter
has been previously lubricated, the plate can be easily removed. If it adheres to the "wall", it can be separated
with the aid of a knife, provided that the latter is used with great caution. W h e n the edge of the glue plate has been
raised from the surrounding "wall", the rest of the plate is carefully removed; as it is flexible, this operation,
which must be effected by hand without the use of any instrument, is not difficult. W h e n the glue plate has been
completely removed, the wax cast should remain intact if the work has been correctly done.
O n reversing the glue plate. the engraving which has been reproduced on it will face upwards. The printing surfaces which were previously in contact with the glass pane must appear smooth, as though they had
been polished. This accuracy in the casting of the glue plate, which is of fundamental importance, depends on the
cleanness of the glass pane and on the avoidance of air-bubbles when the glue is being poured over the wax cast.
-
-
-
T h e printing-plate, which is thus obtained, is placed in its natural position on a flat surface with the engraved face upwards. T h e glue is very flexible and uneven surfaces can distort the plate. If it is so desired,it
m a y be maintained in this position for months.
T h e plate is now ready for printing.
-
18
-
IV. THE PRINTING P R O C E S S
hand.
T h e printing process which is described below does not require a printing-press; everything is done by
At CREFAL w e use cheaply-made presses which are described further on.
INKING
T h e glue printing-plate is very sensitive to ink; it absorbs and transfers the latter very easily. Any kind
of roller (hard or soft) can be successfully used in order to ink the surface of the printing-plate. The roller itself is inked on a glass pane on which the ink has been evenly spread with a spatula.
T h e only difference between the glue printing-plate and most other printing-plates is the degree of pressure exerted on the roller. T h e ink-roller must be moved over the glue plate with the m i n i m u m of pressure; the
m e r e weight of the roller is sufficient.
Any form of printing-ink m a y be used.
PRINTING BY HAND
T h e sheet of paper is placed on the inked plate, care being taken that it does not m o v e after having been
placed on the plate. T h e printer, after gently passing his hand over the paper, carefully removes it by taking
hold of one of its edges. T h e impression thus m a d e will faithfully reproduce the engraving on the plate.
It is possible to obtain an unlimited number of copies by means of this very simple process. At CREFAL
w e have not produced m o r e than a thousand copies at any one time, but after their production the plate has not
been found to have deteriorated in any way.
It m a y sometimes happen that a part of the printing-plate corresponding to a white surface on the poster
is stained with ink during the inking process; this stain will be reproduced on the poster. It can be removed
from the plate by cleaning the latter with a piece of cloth soaked in gasoline.
If such stains keep occurring, they m a y be due not to the inking but to the fact that the hollow corresponding to the white surface is not sufficiently deep. In this case, it is better to deepen the hollow corresponding to
the surface which has been stained by cutting the plate with a small knife.
Once the glue plate has been made, it is no longer possible to alter it. Minor features can be removed
with a knife, but it is impossible to add anything without making a new printing-plate.
CARE A N D C O N S E R V A T I Q N OF MATERIALS
T h e wax used for the engraving, and the mixture of glue and glycerine, can be used indefinitely.
T h e wax shavings which form during the engraving process should not be thrown away. Moreover, when
the wax cast is no longer needed. the wax should be scraped from the glass pane; it can then be melted in order
to m a k e another wax cast, and so on indefinitely.
F r o m time to time the wax should be filtered, so as to remove particles of dust or any other foreign
matter.
Likewise with regard to the mixture of glue and glycerine. W h e n the glue printing-plate is no longer
needed, it should be cut up into small pieces and melted for further use. T h e consistency of the mixture remains
m u c h the same. If it s e e m s too thick, water should be added to it in order to m a k e up for the water that has
evaporated owing to the heat.
A glue plate can last for three months without deteriorating. Nevertheless, it is not advisable to keep it
for such a lengthy period. If it is desired to preserve an engraving, it is preferable to keep the wax cast,which
never deteriorates. A new glue plate m a d e on that cast will serve as a new printing-plate.
- 20 -
THE PRINTING PRESS
W e have already described the process of printing by hand. It is very simple, but it is also slow. In order
to speed up the process, w e have invented a number of simple wooden presses which can be constructed by any
carpenter. Very complicated presses (flat-bed or rotary) can also be m a d e and adapted to printing from a glue
plate.
T h e following is a brief description o f a flat-bed press and of the manner in which it works:
a main table (figure A);
an adjustable bed for the inker or ink-table (B);
an adjustable bed for the glue plate or printing-plate (C);
a thick glass pane (D)(on the ink-table) on which the ink is smeared for the purpose of inking the rollers;
a glue plate (E), placed on the above-mentioned adjustable bed for it and on the s a m e level as the glass
pane for the inking;
adjustable screws (F)which permit the glue plate and the glass pane to be placed on the s a m e level;
which is moved backwards
ink-rollers ( G )which are placed on the ink-table, and a pressure-roller (H)
and forwards over the printing-plate.
T h e printing-press is worked in the following manner:
T h e ink is spread over the glass pane with a spatula. T h e ink-rollers are moved from point Y to point
Z and then back to point Y. W h e n they m o v e over the glass pane (Y to W )they become inked, and when they
m o v e backwards and forwards over the glue plate (W to Z and Z to W ) they transfer the ink to that plate.
When this has been done, a sheet of paper is spread by hand over the glue plate. The pressure-roller (H)
is then moved from point X to point W. Thj5 roller exerts a slight pressure on the paper which is spread over
the inked printing-plate and thus makes an impression on the paper. T h e latter is removed by hand, by taking
hold of one of its edges, and the poster is then ready for use.
If the impression is faulty, it must be corrected by altering the level of the press by means of the adjustable screws.
If certain lines or surfaces on the poster are not satisfactory, they can be corrected by slightly raising
that part of the glue plate which corresponds to the area concerned and inserting a paper wedge underneath it.
Z I
Y
E
/
O\
A
F
- 22 -
/c
c.."
The rollers are moved over the glass pane
in order to ink them. They are then moved
over the glue plate in order to transfer
the ink to that plate.
-
23
-
A SYSTEM USED A T CREFAL
A s a result of our experience at CREFAL, w e have invented, a m o n g others, the printing-press,illustrated
below.
T h e vertical cross-section shows the following parts:
A
Glue plate.
B
Adjustable bed for the glue plate.
C
Screws for adjusting the level.
D
Main table of the printing-press.
E
Supports for the rails.
F
Rails.
G
Blocks supporting the rollers which run along the rails.
H
Roller.
I
Plank connecting the two blocks supporting the rollers.
T h e rails must run right along the printing-press; they should be m a d e preferably of hard wood, so that
they will not warp after constant use. T h e blocks supporting the axles of the rollers must also be of hard wood,
and must fit into the rails as accurately as possible so that they can m o v e along without any jerking motion such
as would destroy the evenness of the pressure.
T h e ink-rollers can be m a d e with the s a m e mixture of glue and glycerine as is used for the printingplate. For that purpose, a hollow, cylindrical mould with a central support for the axle is necessary. T h e rollers can also be m a d e of wood turned on a lathe and covered with cloth of closely-woven wool.
T h e pressure-rollers are m a d e of wood turned on a lathe.
T h e axle of the roller turns in a hole which is m a d e directly in the supporting block ( G ) if the latter is
m a d e of hard wood. If the press is to be used continuously or very frequently, the axles should be placed on
metal axle-boxes.
T h e adjustable bed (B)must be flat and sufficiently strong not to warp. A framework covered with plywood is recommended for that purpose.
E
F
H
G
- 25 -
I
V . APPLICATION TO FUNDAMENTAL EDUCATION
In considering the process of printing from a glue plate and its application in the field of fundamental education, it is important to define its main objects.
The first problem is: Should graphic materials be produced for merely local purposes or for nationwide distribution?
In the latter case, the process described in this booklet would oTfer few advantages. Printing from a
glue plate is a manual and quasi-domestic task, and its quantitative output is not very great. In large-scale
production, it cannot compete with lithography or photo-engraving. If the Ministry of Education of any country
wishes to make posters for nation-wide distribution, the glue plate process is neither economical nor useful.
O n the other hand, in the field of fundamental education, the graphic materials used must correspond to
local conditions.
Posters are useful if they deal with a specific problem and,suggest a satisfactory solution for it. Let US
take the following case as an example:
Malaria is a very widespread problem.
Posters produced at central agencies can merely offer the following advice: "Protect Yourselves from
Mosquitoes". O n the other hand, posters produced locally can make either of the following recommendations:
"Dry up the Swamps'', or "Cover Swamps with Oil",according to their respective degree of feasibility in the
region concerned. Frequently,local conditions require different solutions for the same problem. Posters
produced locally can take these differences into account and so exert a greater effect.
A typical example of this centralized production is offeredby a poster produced and distributed by a
National Health Department. The words on the poster are: "Cover your Windows with Wire-Netting" . The posters were distributed in a region where it was practically impossible to procure wire-netting; consequently, they
had little practical effect. If the poster had been adapted to local conditions, it would have said: "Cover your
Windows with Gauze", a material which was easily obtainable in'theregion concerned.
With locally produced posters it is possible to propose specific solutions, to present visual images with
which the inhabitants of the locality concerned can fully identify themselves. The local inhabitants, especially
those in backward regions, are particularly attached to local traditions and usually identify themselves with
their region or community. In a village on the shore of Lake Patzcuaro, a group of teachers students at
CREFAL exhibited a poster produced at the Centre. This poster showed the correct way of selecting Indian
corn seeds. ..The following conversation between two of the villagers, overheard by the students of the Centre,
contained an interesting piece of criticism.
-
-
"This is how seeds are selected in Guadalajara" said one of them, looking at the poster.
"How do you know that it is in Guadalajara that they select seeds in this way?" asked the other villager.
The first villager answered confidently: "It is quite obvious; this is a picture of Guadalajara. Can't you
see what kind of hat the m a n is wearing?".
gion.
The CREFAL artist had not paid sufficient attention to the style of hat that is worn in the Patzcuaro reIn fact, he had taken as his model a hat that is characteristic of Jalisco.
The poster "Viejito.. . Per0 Aprendiendo", is an example of the possibilities that are offered by local
production. The poster contains a play upon words, as "viejito" (little old man) is a1so.a character of a tradi:
tional folk-dance, which is known to all the men, w o m e n and children of the Patzcuaro region. Outside of this
region it is little known, so that this poster, exhibited anywhere else, would give rise to confusion or lose its
point.
The clothes, colour, customs, architecture, landscape and many other details depicted on a poster determine the extent to which the inhabitants can identify themselves with it and its ideas.
Sometimes it is not feasible to produce different posters for the hundreds of different localities in
Mexico, as each of them has its own style of hats, dances, etc. Nevertheless, we feel that posters should
correspond to local conditions so far as possible.
- 27 -
Another important factor is the independence of local production. The greater the number of persons to
w h o m the means of reproduction are available, the more democratic will be the results.
It is probable that posters and similar graphic materials intended for local exhibition will reflect the
true needs and aspirations of the local inhabitants if they are evolved, from first to last, by the local teachers
and authorities. rather than by officials living some hundreds of kilometres away.
In the case of local production, the process of printing from a glue plate offers many advantages. It can
be employed with a minimum of equipment. When the glue plate (or printing-plate)has been made, all that is
necessary is an ink-roller in order to make impressions... The only object of a printing-press is to speed up
production. Unlike other printing processes, this process requires only a minimum of pressure for the making
of impressions. The glue plate, which is very flexible, makes an ink impression on the paper very easily.
Without a printing-press it is possible to print from a glue plate five or ten times as quickly as from a linoleum
or a wood plate.
It is also possible to make very large posters. The size of the poster is only limited by the size of the
glass pane that is available. A glue plate measuring 2 x 2 metres can be made just as easily as the smallest
plates. The glue plate is placed on a large table (or even on the ground), it is inked with a hand-worked roller,
and the impressions are made by placing the paper on the glue plate and lightly smoothing it out.
Coloured posters can also be printed; a different plate is made for each colour, exactly as in any other
printing process.
As the plate is very flexible, it can also be used on a rotary printing-press; for that purpose it is sufficient to place the plate around a cylinder and to fix the latter in its right position.
A s one of the main characteristics of the glue plate is its flexibility, different kinds of printing-presses,
made entirely of wood, can be constructed. This is possible owing to the slight pressure needed in making the
impressions, and to the fact that the printing-pressesdo not have to be constructed with very great precision.
The flexibility of the glue plate makes up for any defects in the printing-press. If the rollers are defective, the
pressure uneven or the table warped, or if there are other imperfections, these do not prevent good results
from being obtained. Consequently. any teacher, aided by a carpenter, can construct his own press at very
little cost.
Fundamental Education workers frequently have occasion to print words with very large letters. It is difficult to find type more than three inches in size; large type, moreover, is very expensive. Our printing process makes it easy to engrave letters of any size on the wax plate and then to print them from glue plates.
Another advantage of the flexible plate is that it is possible to make impressions from it on any kind of
material. At the Centre w e have successfully printed on cloth, wood, leather, glass, metal, cement and plaster,
as well as on various kinds of paper. The flexibility of the plate permits it to be adapted to almost all surfaces,
provided that these are able to absorb the ink.
Dress patterns of normal size can be printed on the material to be cut out. Permanent advertisements
can be printed on wood or metal. Flags and banners can be printed on cloth.
A s the needs of Fundamental Education workers vary considerably, printing on different materials offers
considerable scope.
While the technical features of the process provide the many advantages which w e have mentioned,several
of the teachers studying at the Centre consider that the chief advantage is its low cost, together with the availability of the materials.
After the initial outlay for the glue, glycerine and wax, it is possible to continue to print different posters
for an indefinite period without further expense. If the glue is kept clean, its quality improves with use, instead
of deteriorating. Frequently it is necessary to print only a hundred posters or less. The expense of making a
printing-plate by most of the other processes is so high that the cost of printing even so small a number of posters
would be prohibitive.
Apart from the work done by the teacher, it costs nothing to make a glue plate. This process is therefore a practical one, even though it be used for producing only from ten to fifteen copies of a poster.
Of all the other printing processes, cerotype is the only one which offers much the same advantages as
the glue plate procedure. Nevertheless, those familiar with cerotype consider that printing from a glue plate
offers greater possibilities.
People working daily in the field of Fundamental Education are continually confronted with new problems.
which require new solutions. It is to them that w e offer this printing process. If they apply it patiently and
assiduously, they will soon see their efforts rewarded.
This has been our own experience,and w e would like it to be that of many other Fundamental Education
teachers.
- 28 -
UNESCO COUPONS
W e should like to draw the attention of our readers to this s c h e m e , w h i c h m a y enable
t h e m to purchase materials listed in this periodical. B e c a u s e it is often difficult to
s e n d m o n e y from country to country for the purchase o f books, films, laboratory equipment, etc., U n e s c o has created a sort of international currency, the UNESCO COUPON.
T h e s e coupons enable schools, universities, teachkrs and students in m a n y parts of
the world to buy freely the materials w h i c h they need for study and research.
UNESCO COUPONS
can be used to buy:
books
periodicals
the following categories of educational films :
photocopies
microfilm copies
(a) screening prints and duplicate
prints
art reproductions
charts, globes, maps
sheet music
gramophone records
The
(b) original negative and duplicate
negatives
(c)
optical instruments, balances and
weights
laboratory glass-ware
as well as
electrical measuring instruments
16 mm. raw film for printing the
above categories of films,
UNESCO COUPON SYSTEM
AUSTRIA
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CANADA
CEYLON
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various categories of scientific
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such as :
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apparatus,etc.
clinical testing
operates in the following 32 countries :
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HUNGARY
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O F AMERICA
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YUGOSLAVIA
Non-self-governingterritories m a y obtain coupons through their administerlng countries,
Detailed information o n the use o f
ing explanatory leaflets :
UNESCO COUPONS
is contained in the follow-
T H E UNESCO BOOK COUPON
T H E UNESCO FILM COUPON
T H E UNESCO COUPON FOR SCIENTIFIC MATERIAL
T h e leaflets m a y be obtained u p o n request from the:
UNESCO COUPON OFFICE
19, avenue Kle'ber,
PARIS XVIO
-
FRANCE
UNESCO PUBLICATIONS : NATIONAL DISTRIBUTORS
ARGENTJNA
Editorial Sudamericana,
S.A. Alsina 500,
B U E N O S AIRES.
ASSOCIATED STATES OF
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VIET-NAM
Librairie Nouvelle,
A. Portail.
Boite Postale 283
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Sub-depot:
K. Chantarith, CCR.,
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Oxfoxd University Press,
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AUSTRIA
Wilhelm Frick Verlag,
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S.P.C.K. Bookshop,
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Librairie EncyclopCdique,
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Libreria Selec cione s,
Ave. 16 de Julio 216,
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Livraria Agir Editora,
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Caixa Postal 3291,
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CANADA
University of Toronto Press,
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The Lake House Bookshop,
The Associated Newspapers
of Ceylon Ltd.,
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COLOMBIA
Emilio Roy0 Martin,
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CUBA
-
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NArodni 37, P R A G U E
I.
DENMARK
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ECUADOR
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L a Renaissance d’Egypte,
9 Adly Pasha Street, CAIRO.
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Akateeminen Kirjakauppa,
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FORMOSA
The World Book Co.,
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1st Section, TAIPEH.
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Unesco Bookshop,
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Saraster’s Book Room.
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Maruzen CO.,Inc.,
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Joseph I. Bahors & CO.,
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Libralrie Universelle,
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AND SINGAPORE
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GERMANY
Unesco Vemieb fik Deutsch
land, R. Oldenburg,
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HAITI
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Unesco Publications Centre,
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I .
Kultura, P.O. Box
B U D A P E S T 62.
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McKenzie’s Bookshop,
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Blumsteh’s Bookstores Ltd.,
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Orbis,
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A/S Bokhjdrnet,
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Agencia Internacional de
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Philippine Education Cp.,hc.,
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Publicaqoes Europa-America
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Pan-American Book
S A N J U A N 12..
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2,
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Librairie Universelle,
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Centre International,
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Suksapan Panit, Arkarn
Rajdamnern Avenue,
BANGKOK.
9,
TUNISIA
~~
~~~~~
Agence AghlCbite,
20 Grand-Rue,
Postal address; B.P. 2,
KAIROUAN.
TURKEY
Librairie Hachetre,
469 Istiklal Caddesi,Beyoglu,
ISTAMBUL.
UNION OF BURMA
Bunna Educational Bookshop,
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Van Schaik’s Bookstore
(Pty)Ltd., P.O.BOX 724,
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Jugoslovenska Knjiga,
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BELGRADE
EDUCATIONAL STUDIES A N D D O C U M E N T S
A limited number of copies are available free eo workers in education,and
may be obtained on application to Unesco's Education Clearing House
I
- Report
11
- ,4fricm Languages and English in Education
on the Unesco L a Breviere International Seminar on Workers' Education, 1952,
by G.D.H. Cole
(also in French and Spanish)
(also in French)
I11
-
IV
- BLlateral Consultations for the Irnprovenient o f Flrstory
llozo to Print Posters, b y Jerome Oberwager
(also in French)
7exthooks
(also in French)
V
- Methods o f Teaching Reading and Writing: a preliminary survey, by W.S.Gray
(also in French and Spanish)
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